在体外通过人类CDC25蛋白质去化和激活p34cdc2/cyclin B复合体
U Strausfeld1, J C Labbé, D Fesquet
1CNRS and INSERM, BP 5051, Montpellier, France.
Nature
|May 16, 1991
概括
研究人员确定了一种激活细胞分裂的关键蛋白质. 人类的CDC25蛋白消并激活p34cdc2/cyclin B复合体,促进细胞周期从G2到M阶段的过渡.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 卵细胞在G2阶段与非活性p34cdc2/cyclin B复合体一起被捕.
- 这种复合物通过在p34cdc2.2.上的酸化被非活性化.
- 调节这种作用的酸酶是未知的,但CDC25是可能的激活剂.
研究的目的:
- 研究CDC25在激活p34cdc2/cyclin B复合体中的作用.
- 为了确定人类CDC25是否可以激活复合体在体外.
主要方法:
- 从海星卵细胞中净化非活性p34cdc2/cyclin B复合体.
- 在体外测定使用纯化的细菌表达人体p54CDC25H.
主要成果:
- 添加p54CDC25H引发了p34cdc2脱.
- 复合物的p54CDC25H激活的H1基因素激酶活性.
结论:
- cdc25+基因产物直接激活了p34cdc2-环林B复合体.
- 人类p54CDC25H可以功能地激活海星卵细胞p34cdc2-环素B复合体.
相关概念视频
01:45Positive Regulator Molecules
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02:39Positive Regulator Molecules
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